Data transmission method and data transmission apparatus

Abstract

This application provides a data transmission method and a data transmission apparatus, which can establish a radio bearer for a data plane based on a new wireless network architecture (i.e., a network architecture in which a control plane and a user plane are separated) to implement data transmission. The method includes: a terminal device sends selection information to a control plane access network device, where the selection information indicates a target user plane access network device, which is determined from at least one user plane access network device based on system information and a user plane access network device selection rule. The terminal device receives first timing advance information and first radio bearer configuration information from the control plane access network device, and performs data transmission with the target user plane access network device based on the first timing advance information and the first radio bearer configuration information.

What is claimed is: 
     
         1 . A data transmission method, comprising:
 sending, by a terminal device, selection information to a control plane access network device, wherein the selection information indicates a target user plane access network device, and the target user plane access network device is determined from at least one user plane access network device based on system information and a user plane access network device selection rule;   receiving, by the terminal device, first timing advance (TA) information and first radio bearer configuration information that are from the control plane access network device, wherein the first TA information indicates a TA value of the terminal device on the target user plane access network device, and the first radio bearer configuration information indicates a data radio bearer (DRB) allocated by the target user plane access network device to the terminal device; and   performing, by the terminal device, data transmission with the target user plane access network device based on the first TA information and the first radio bearer configuration information.   
     
     
         2 . The data transmission method according to  claim 1 , wherein the sending, by the terminal device, selection information to the control plane access network device comprises:
 sending, by the terminal device, a random access preamble to the control plane access network device, wherein the random access preamble indicates the target user plane access network device.   
     
     
         3 . The data transmission method according to  claim 2 , wherein the receiving, by the terminal device, first timing advance TA information from the control plane access network device comprises:
 receiving, by the terminal device, a random access response (RAR) message from the control plane access network device, wherein the RAR message comprises the first TA information.   
     
     
         4 . The data transmission method according to  claim 3 , further comprising:
 sending, by the terminal device, a radio resource control (RRC) connection setup request message to the control plane access network device.   
     
     
         5 . The data transmission method according to  claim 4 , wherein the receiving, by the terminal device, the first radio bearer configuration information from the control plane access network device comprises:
 receiving, by the terminal device, an RRC connection setup message or an RRC connection reconfiguration message from the control plane access network device, wherein the RRC connection setup message or the RRC connection reconfiguration message carries the first radio bearer configuration information.   
     
     
         6 . The data transmission method according to  claim 2 , wherein a random access resource of the control plane access network device corresponds to the at least one user plane access network device, and wherein the random access preamble is sent on a random access resource corresponding to the target user plane access network device. 
     
     
         7 . The data transmission method according to  claim 3 , further comprising:
 sending, by the terminal device, a random access preamble to the control plane access network device; and   receiving, by the terminal device, a RAR message from the control plane access network device,   
     
     
         8 . The data transmission method according to  claim 5 , wherein the sending, by the terminal device, selection information to the control plane access network device comprises:
 sending, by the terminal device, an RRC connection setup request message to the control plane access network device, wherein the RRC connection setup request message comprises the selection information.   
     
     
         9 . The data transmission method according to  claim 8 , wherein the receiving, by the terminal device, first timing advance TA information and first radio bearer configuration information that are from the control plane access network device comprises:
 receiving, by the terminal device, an RRC connection setup message or an RRC connection reconfiguration message from the control plane access network device, wherein the RRC connection setup message or the RRC connection reconfiguration message comprises the first TA information and/or the first radio bearer configuration information; or   receiving, by the terminal device, an RRC connection setup message and an RRC connection reconfiguration message that are from the control plane access network device, wherein the RRC connection setup message comprises the first TA information, and the RRC connection reconfiguration message carries the first radio bearer configuration information.   
     
     
         10 . The data transmission method according to  claim 4 , wherein the RAR message further comprises second TA information, and the second TA information indicates a TA value of the terminal device on the control plane access network device, and
 wherein the RRC connection setup message further comprises second radio bearer configuration information, and the second radio bearer configuration information indicates a signaling radio bearer SRB allocated by the control plane access network device to the terminal device.   
     
     
         11 . A data transmission apparatus, comprising:
 a memory;   a processor coupled to the memory and configured to   send selection information to a control plane access network device, wherein the selection information indicates a target user plane access network device, and the target user plane access network device is determined from at least one user plane access network device based on system information and a user plane access network device selection rule;   receive first timing advance (TA) information and first radio bearer configuration information that are from the control plane access network device, wherein the first TA information indicates a TA value of the apparatus on the target user plane access network device, and the first radio bearer configuration information indicates a data radio bearer (DRB) allocated by the target user plane access network device to the apparatus; and   perform data transmission with the target user plane access network device based on the first TA information and the first radio bearer configuration information.   
     
     
         12 . The apparatus according to  claim 11 , wherein the processor is further configured to send a random access preamble to the control plane access network device, wherein the random access preamble indicates the target user plane access network device;
 receive a random access response (RAR) message from the control plane access network device, wherein the RAR message comprises the first TA information;   send a radio resource control (RRC) connection setup request message to the control plane access network device; and   receive an RRC connection setup message or an RRC connection reconfiguration message from the control plane access network device, wherein the RRC connection setup message or the RRC connection reconfiguration message carries the first radio bearer configuration information.   
     
     
         13 . The apparatus according to  claim 12 , wherein a random access resource of the control plane access network device corresponds to the at least one user plane access network device; and
 the random access preamble is sent on a random access resource corresponding to the target user plane access network device.   
     
     
         14 . The apparatus according to  claim 11 , wherein the processor is further configured to send a random access preamble to the control plane access network device;
 receive a RAR message from the control plane access network device;   send an RRC connection setup request message to the control plane access network device, wherein the RRC connection setup request message comprises the selection information; and   receive an RRC connection setup message or an RRC connection reconfiguration message from the control plane access network device, wherein the RRC connection setup message or the RRC connection reconfiguration message comprises the first TA information and/or the first radio bearer configuration information; or receive an RRC connection setup message and an RRC connection reconfiguration message that are from the control plane access network device, wherein the RRC connection setup message comprises the first TA information, and the RRC connection reconfiguration message carries the first radio bearer configuration information.   
     
     
         15 . The apparatus according to  claim 12 , wherein the RAR message further comprises second TA information, and the second TA information indicates a TA value of the apparatus on the control plane access network device, and
 wherein the RRC connection setup message further comprises second radio bearer configuration information, and the second radio bearer configuration information indicates a signaling radio bearer (SRB) allocated by the control plane access network device to the apparatus.   
     
     
         16 . A non-transitory computer-readable storage medium storing computer instructions, that when executed by one or more processors, cause the one or more processors to perform steps of:
 sending selection information to a control plane access network device, wherein the selection information indicates a target user plane access network device, and the target user plane access network device is determined from at least one user plane access network device based on system information and a user plane access network device selection rule;   receiving first timing advance (TA) information and first radio bearer configuration information that are from the control plane access network device, wherein the first TA information indicates a TA value of the terminal device on the target user plane access network device, and the first radio bearer configuration information indicates a data radio bearer (DRB) allocated by the target user plane access network device to the terminal device; and   performing data transmission with the target user plane access network device based on the first TA information and the first radio bearer configuration information.